An input device for input of alphanumeric characters into a computer, is known from DT-AS 22 35 620. The device has a character input zone in the form of a panel having sensors together with additional function keys, as well as logic and memory means in which the signals from the sensors are stored and scanned in a predetermined sequence for recognition of the characters. The device is used for the manual input of letterpress, alphanumeric character sequences as well as command codes into electronic computers. This known input device is a stationary input apparatus connected integrally with the computer. The sensors in the input zone are so chosen in number and arrangement that each input character can be clearly recognized solely by the combination of the sensors touched at input. In order to ensure this freedom from ambiguity a relatively large number of sensors is necessary. The sequence in which the sensors are touched while writing is unimportant and is not recorded. In the recognition of the character, the stored signals from the sensors are scanned in a certain sequence, and the sequence in time of the writing of a character can no longer be recognized. Moreover, the input zone of the device is such that a stylus must be employed for the input of the characters.
An object of the invention is to provide a character input device requiring only three or four sensors. A further object of the invention is to provide a character input device which can be used by relatively unskilled persons.
Another object of the invention is to provide a character input device of compact and simple, and consequently inexpensive construction.
An additional object of the invention is to provide a character input device capable of responding correctly to characters written in a variety of styles.
Yet another object of the invention is to provide a character input device which is portable and free of wired connection to the apparatus to which character representing signals are supplied.